Unlocking the secrets behind brain food
There is a lot of research focused on how adopting a diet full of ‘brain foods’ can slow down cognitive ageing – with claims even going so far as reducing your risk of dementia. So, what is the link between the food we eat and brain function?
The idea of brain food is nothing new – in fact, we’re often told by our parents growing up that certain foods will have a positive impact on the development of our brains, but how much of what we’ve been told actually stands up to scrutiny? Could it all just be old wives’ tales?
It would seem to follow that the nutrients we consume through the food we eat would have a large impact on the function of our brains, but rather than just accepting that assumption, we’ll be looking at the facts and the science behind the idea of brain food. It has been suggested that particular foods, such as those which contain Omega-3, have a positive effect on cognitive health – but does this have as big of an impact as some would have us believe?
This article, based on our podcast “How does what you eat affect brain function?” explores what the research about brain food actually tells us and the best food for the brain in order to keep our brains as healthy as possible for as long as possible.
We spoke to Anne-Marie Minihane, Professor of Nutrigenetics and Head of Nutrition and Preventive Medicine in the Norwich Medical School at the University of East Anglia about the impact food can have on Dementia, how what we eat can have an effect on short-term cognitive function and how you go about getting people to change their diets for the better.
What is brain food? An overview of cognitive nutrition
With all the current buzz about whether or not diet can slow down the process of cognitive ageing, even going so far as reducing the risks of developing dementia, what exactly is cognitive nutrition? The idea of brain food is nothing new, it’s what we’re told by our parents while we’re growing up so that we have a healthy development, but how much of what we’re told is really true? What should we be eating in order to keep our bodies and minds healthy?
Professor Anne-Marie Minihane explains that, though cognition is an umbrella term for a wide range of processes within our brains and bodies, nutrition can influence how our brain works as a whole.
“Cognition is kind of an umbrella term, which describes a whole host of mental processes. Things like language, attention, memory, processing, speed and executive function, which is our ability to accumulate information and make sense of it and make decisions. So it’s kind of an umbrella term, which explains the performance of the brain. And of course, nutrition cognition is the influence of what we eat from the point of conception, right through life, and how that influences how our brain works.”
So, just how significant is nutrition on cognitive function? Professor Minihane says that, because the gut acts as a sort of second brain, with shared neurotransmitters and all, nutrition provides a very strong influence on cognitive function.
“The brain only makes up about 2% of our body weight, but it uses 20% of the oxygen we consume. It uses 20% of the glucose that we need for our body. The brain needs about 1100 litres of blood per day, so the brain is an amazing organ and extremely sensitive to what it is provided with by way of nutrition and diet.
“The gut is known as the second brain, as it is full of neural connections and neurons. There’s a really strong influence of gut health on cognitive health and brain health, and that’s modulated through a host of processes.
“At a neural level, the vagus nerve connects the gut to the brain. Also, the brain produces a whole host of neurotransmitters which affect brain function. The gut is a really important determinant of inflammation, systemic inflammation, and the effects of neuroinflammation, and this is really important for brain function”.
How can you get the most out of good brain food?
What are the factors that are at play when it comes to good brain food providing cognitive benefits? Could it be an overall thing that nutrition has an effect on our weight, blood pressure, immune system, and more; or do we just need to have a healthy diet and lifestyle for our brains to even work in the first place? Perhaps there’s a particular chemical that, when you metabolise it, has an influence on how your brain works.
Professor Minihane states that the brain is very sensitive to gut and cardiovascular health. As many of our nutritional approaches have a benefit on our cardiovascular health this, in turn, will have a positive impact on our cognitive health, leading to a lower risk of developing Alzheimer’s.
“So, is the effect of nutrition on the brain secondary, or is it a primary and direct effect on the brain? I think it’s very much both. The brain is very, very sensitive, to gut health and to cardiovascular health, so it could be that a lot of our nutrition approaches or interventions are actually improving cardiovascular health, which increases blood flow to the brain, which will have a knock-on effect on cognitive health.
“We also know that a lot of dietary components cross the blood-brain barrier, and directly affect brain function through things like improving the functionality of the neuron, reducing neuroinflammation, and things like glial cells, which are like the immune cells of the brain, and are very sensitive to nutrition. [Direct and indirect effects], both are equally important.
“In things like the heart, the liver, or the gut [and other tissues in the body], DHA, [or Docosahexaenoic acid, which is an omega-3 fatty acid], makes up about four to 5% of total fatty acids in the brain, it makes up about 15% of total fatty acids [in the body]. In certain brain regions, such as the synaptic regions where neurons talk to each other, it can actually make up about 40% of fat in those regions. So it’s incredibly important for brain function, and it’s a major structural component of neurons.
“The regions of the neurons which talk to synapses and produce neurotransmitters are very dependent on DHA as DHA regulates neuroinflammation. One of the main proteins which accumulate in the brain, if you have the Alzheimer’s form of dementia, is amyloid plaques, and DHA is incredibly important in how much of the plaque we produce, and also the clearance of the plaque”.
Is brain-healthy food and nutrition universally beneficial?
Although good nutrition may be universally beneficial, there are subgroups of the population that are more likely to respond to better nutrition than others. Professor Minihane explains that those who increase their intake of nutritious foods after having a particularly poor diet are more likely to see benefits over time than someone who is a ‘nutrition repeat’ – someone who already has a nutritious diet.
“Nutrition is probably universally beneficial to all, but there are subgroups which are more likely to be responsive. If you have a poor nutrition status to begin with, then you’re likely to attain more cognitive benefits than if you’re what we call nutrition repeat.
“We’re also very interested in a particular gene called the APL E4 gene. If you’re an AP carrier, which is about 25% of the population, you’re four times more likely to develop dementia; and it’s often associated with earlier age of onset. This is the most prevalent genetic risk factor for cognitive decline and dementia, and there’s been a lot of interest in whether if you’re an E4 carrier, are you more or less responsive to intervention.
“The evidence is that, whether you’re an E4 carrier or not, you will still gain benefits from good nutrition, but, with certain things you eat, you might gain extra benefits because you’re at increased risk relative to the rest of the population. Nutrition is beneficial in everyone, regardless of your age or your genotype, but I think if you’re at risk, or you’re in a state of nutrition deficit, to begin with, then you’re likely to gain more benefit”.
Does supplemental brain food work?
Supplementing appears to work in order to receive a number of health benefits when certain nutrients aren’t obtained in sufficient quantities from diet alone – but does supplementing work for cognitive health? Professor Minihane explains that you should, where possible, get your nutrients from food as that is already designed by nature to ensure nutrients are absorbed properly by the body, but supplements can be used where food consumption is a problem for people.
“I would always recommend supplements for particular groups. So for example, if you’re in an elderly group where appetite is a problem, then certainly a supplement is a good way to get those nutrients we’re talking about. If you’re recovering from illness, and you can’t really consume too much food, then again, supplements are a good thing. For most of us, food is a much more effective way of getting those bioactive nutrients, and it kind of makes sense because nature has provided these things in the correct format and the correct doses relative to each other.
“The problem with supplements is you’re often consuming dietary components at really high levels relative to how they’re present in the diet naturally, and these can have knock-on effects on how we absorb other nutrients from food. Also, the structure of food is really well set up to ensure that the components are absorbed properly and that they actually made their way into the bloodstream.“
But what about Omega? Can this be supplemented effectively, or are there certain benefits that can only be obtained after eating foods rich in Omega-3 compared to supplementing? Professor Minihane explains that many of the benefits of Omega-3 come from fish, which is a very complete food source in itself.
“Most of the evidence for the benefits of Omega-3 comes from fish because, at a population level, most of our Omega-3 will have traditionally come from fish. Now fish, particularly oily fish, is a very complete food. So it’s got good quality protein, certain fish are high in vitamin D, selenium hydrate, Vitamin B 12 and Omega-3s. So, all of these components are good for brain health. If you eat your Omega-3 as fish, you don’t want to just get the omegas, you get all of those other beneficial dietary components as well”.
6 of the best brain foods for a boost to your brain and memory
The foods you eat play a vital role in keeping your brain as healthy as possible, even going so far as helping to improve specific cognitive tasks like memory and concentration.
So, what are the best foods that are healthy for the brain?
When it comes to discussions about brain food, fatty and oily fish is often a primary topic of discussion as some of the healthiest brain foods. These types of fish include salmon, trout, albacore tuna, herring, and sardines – all of which are rich sources of Omega-3 fatty acids.
About 60% of your brain is made of fat, and half of that fat is derived from Omega-3 fatty acids. Your brain uses this to build essential structures in the brain, too, such as brain and nerve cells and even grey matter – which contains most of the nerve cells that control decision-making, memory, and emotion. Furthermore, not only are these fats essential for learning and memory, but they may also aid in slowing mental decline, ward off Alzheimer’s disease, and fend off depression.
Coffee isn’t only the highlight of many people’s mornings, it can also be pretty good for you! Two of the main components of coffee, caffeine and antioxidants, are able to support brain health. In addition, the caffeine found in coffee has a number of positive effects on the brain, such as:
- Increased alertness: Caffeine keeps your brain alert by blocking adenosine, a chemical messenger which makes you feel sleepy.
- Improved mood: Caffeine may also provide a boost to some of your feel-good neurotransmitters – such as dopamine.
- Sharpened concentration: One study found that caffeine consumption led to short-term improvements in attention span and alertness in participants completing a cognition test.
Drinking coffee over a long period of time has also been linked to a reduced risk of developing neurological diseases like Parkinson’s and Alzheimer’s.
Blueberries provide a number of health benefits, some of which are specific to the benefit of your brain. Blueberries and other deeply coloured berries deliver anthocyanins, a group of plant compounds which contain anti-inflammatory and antioxidant effects. This can act against both oxidative stress and inflammation which can contribute to brain ageing and the development of neurodegenerative diseases.
Turmeric is a deep-yellow spice which is a key ingredient in curry powder and a primary spice in many curry-style dishes. It also has a number of benefits on the brain due to the presence of curcumin, which has been shown to cross the blood-brain barrier and directly benefit the cells within. It is a potent antioxidant and anti-inflammatory compound which has also been linked to the following brain benefits:
- Memory improvements: Curcumin may help to improve memory in people with Alzheimer’s whilst also helping to clear amyloid plaques – a hallmark of this disease.
- Eases depression: Curcumin boosts serotonin and dopamine which helps to improve mood. One review found that this antioxidant could also improve symptoms of anxiety and depression when used alongside standard treatments.
- Helps new brain cells to grow: Curcumin also boosts brain-derived neurotrophic factor, a type of growth hormone which helps brain cells to grow and may even help to delay age-related mental decline.
Packed with powerful plant compounds and antioxidants, broccoli contains abundant levels of vitamin K, a fat-soluble vitamin which is essential for the formation of sphingolipids; a type of fat which is densely packed into brain cells. A higher intake of vitamin K has been linked to better memory and cognitive status whilst also boasting anti-inflammatory and antioxidant effects, which may help protect the brain against damage.
Containing powerful antioxidants which protect the body and brain from free-radical damage, pumpkin seeds are also an excellent food for brain fog as they are a source of magnesium, iron, zinc, and copper – which are all important for good brain health.
- Zinc: Zinc is crucial for effective nerve signalling, and a deficiency in zinc has been linked to a range of neurological conditions such as Alzheimer’s, depression, and Parkinson’s.
- Magnesium: Essential for learning and memory, low levels of magnesium are linked to a number of neurological issues like migraines, depression, and epilepsy.
- Copper: Your brain uses copper to help control nerve signals – meaning that, when your copper levels are low, there’s a higher risk of developing neurodegenerative disorders.
- Iron: A deficiency in iron is typically characterised by increased brain fog and impaired brain function.